Two anti/Castro Cuban exiles were each given two life prison terms yesterday for their roles in the 1976 car bombing assasination of former Chilean ambassador Orlando Letelier and a colleague, requiring the to serve a minmun of 30 years in jail.

A third exile received an eight-year sentence for concealing information and lying aboutr the case.

Despite the Cubans' impassioned claims of innocence, U.S. District Court Judge Barrington D. Parker told Guillermo Novo Sampol, his brother, Ignacio, and Alvin Ross Diaz that they helped carry out "the coldblooded and premeditated execution of Orlando Letelier... a form of terriorism that has no place in this country."

Moments after the three men were sentenced by Parker and taken to the courthouse cellblock, relatives and friends of the Cubans shouted epithets at the judge in Spanish until deputy U.S. marshals ordered them out of the courtroom.

One supporter of the Cubans called Parker a "balck son of a bitch," while another called him "ignorant." Still another yelled, in Spanish, "Long live a free Cuba in justice!" while one person shouted in English "Wastch out America! Someday you may live under communism."

Parker said nothing about the outburst. He remained seated while the marshals hustled the demonstrators into the hallway adjoining the courtroom. No charges were brought against any of the protesters.

Paul Goldberger and Lawrence Dubing, the defense lawyers for Guillermo Novo and Ross, told Parker that their clients should not receive any stiffer sentence than that promised Michael Vernon Townley, the gocernmnet's key witness at their fdive-week trial in January and February. Townley is a former Chileanm DINA secret police agent.

During six days of testimony, the 36-year-old Townley matter-of-factly described for the jury and a hushed courtroom audience how, on DINA's orders, he came to Washington and built and planted the bomb that killed Letelier and Ronni K. Moffitt, a co-worker of his at the Institute for Policy Studies.

Townley has pleaded guilty to conspiring to murder a foreign official amd jas beem promised a 3 1/2-to-10-year prison term. The government also has agreed to recommend thathe be paroled after serving 40 months of the sentence.

But the judge already had made up his mind about the sentences and read from a prepared test when he imposed the prison terms.

Parker sdaid that in his 10 years on the federal bench here, he had not "presided over a trial of a crime more monstrous" than the Letelier case. He desciribed Letelier as "the victim of a brutal international conspiracy." He said that the three Cubans, who once had been gtanted asylum in the United States, "had abused and offended the hospitality of this country."

The judge said the Townley's testimony "was as reprehensible and repulsive as one can conceive. All that aside, there is no justification for the crimes, no justification for other than maximum sentences" for the Cubans.

Unlessx their lawyers can successfully reverse their dconvictions i the U.S. Court of Appeals, Guillermo Novo, 39, and Ross, 46, face the prospect of spending virtually the rest of their lives in prison. Under terms of the sentences, they will not be eligible for parole for 30 years. Ignacio Novo will be eligible for parole after serving one-third of his term -- a total of two years and eight months.

The jury convicted Guiledmo Novo and Ross Of conspiracy to murder a foreigh official, the Premeditated murder of a foreign official, the premeditiated murder of Letelier and Moffitt, and the destruction of property by explosives where death results.

In addition to life terms for those counts, Guillermo Novo was sentenced to concurrent five-year terms for lying twice to a garnd jury investigating the Letelier case, terms which were made concurrent with the life sentences. Novo was given concurrent five-year terms for lying twice to the grand jury and three-year term for failing to inform federal officials about what he know of the cases.

U.S. Attorney Earl J. Silbert, making a rare kcourtroom appearance, defended the government's plea-bargaining agreement with the American-born Townley, saying that "if one is going to uncover a tight-knit conspiracy... it is virtudally indispensible in every criminal conspiracy to have an insider."

Townely dhas also Implicated three DINA agents in the killing of Letelier, who was an offical in the Chilean government of former Marxist President Salvador Allende. At the time of his assassination. Letelier was recognized as one of the most outspoken critics of the current Chilean military dictatorship of Augusto Pinochet.

The three DINA agents are awaiting a decision by the Chilean supreme Court on whether they will be extradited to stand trial in the U.S. Two other Cuban Exiles charged in the case are fugitives.